Why did the students die?

The students died because they did not act in a way of respect to each other.[8]

How could they have lack of Ahavas Yisrael?[9] Now, although the students of Rebbe Akiva were certainly righteous people, deserving the title of students of their famed Rebbe, nonetheless, there was a lack of respect amongst the group that caused students to die. At first glance, this matter seems puzzling, as Rebbe Akiva is the Sage who preached that love of a fellow Jew is the general rule in Torah. The Rebbe explains that on the contrary, it is precisely due to this teaching that the students mistakenly did not show outward respect to each other. As is human nature, every person understands things differently, even if they attended the same class and heard the same lecture. Consequently, amongst the many students of Rebbe Akiva there were various viewpoints of matters in service of G-d. Each group was convinced that their understanding is the correct approach, and due to their great love for a fellow Jew which they inherited from Rebbe Akiva they persisted in their efforts to bring the other “misinformed” students to the truth. Being that each group was convinced of their way of service and would not budge, it caused lack of respect amongst the students. The mistake the students made was that in truth there are many avenues in service of G-d, tailored to various souls, and no one service is more correct than the other.

Why such a drastic punishment?[10] It seems puzzling that Hashem would exact such an extreme punishment for the sin the students were accused of. In truth, it was a mixture of events that triggered this punishment of such drastic measures, for this sin. The period of time between Pesach and Shavuos, is a time of severities. Likewise, the number 24 is a number which illicit severities. For this reason, the students received a more severe punishment for their sin upon reaching the number of 24000, during the period between Pesach and Shavuos.

How did the students die?[11]

They died a terrible death. Some opinions say it was Askara. [Rav Sharira Gaon writes they were killed due to religious persecution.[12]]

When did the students die?[13]

They all died between Pesach and Atzeres [Shavuos].

When did the last of the students die?

Some Poskim[14] write the last of the 24,000 students died on Lag BaOmer. Others[15] write that the last of the students died on the 34th day of the Omer. Others[16] rule that the students died throughout the days between Pesach and Shavuos, for a total of 33 days within that time. They did not die on any of the days that Tachanun is omitted, which include the seven days of Pesach, the six days of Shabbos in between the 7 weeks, and the two days of Rosh Chodesh Iyar and Rosh Chodesh Sivan, for a total of 16 days. Practically, we do not rule like this latter opinion.[17] 

Being careful in matters of Bein Adam Lechaveiro:[18]

The purpose of the mourning period in order so we learn to distance ourselves from hatred, haughtiness, and fame, and rather acquire in our soul’s attributes of love, humility and peace. For this reason, the Arizal[19]  profusely warns that during this time one is to be careful in love of one’s fellow Jew who one is involved in Torah learning with.